A variety of processes have been employed to remove residual oil from metal parts so that the cleaned parts can later be reused in a mill. One such process includes exposing the oil covered metal parts to high heat, such as by placing the parts in a furnace, to burn off the residual oil. This process for removing the oil has been found to be undesirable in that hydrocarbons are emitted into the air during burning, causing environmental concerns.
It is also known in the prior art to submerse the oil coated parts into a solvent suitable for dissolving the oil. However, this process has been found to present environmental concerns as well in that the used oil-contaminated solvent must be disposed of.
To overcome these environmental concerns, comminuted or ground corncob has been employed. Comminuted corncob material has been found to have good oil absorbing capability. Thus, comminuted corncob material is mixed in with oil-coated parts to bring the corncob material into contact with the oil whereby the oil is absorbed into the corncob material. A significant amount of the comminuted corncob material adheres to the oil-coated parts during mixing and continues to adhere to the parts following the completion of mixing. Mills require that scrap metal be clean, without residual oil or other material thereon. Thus, while comminuted corncob has been found to adequately remove the residual oil in an environmentally safe manner by mixing the comminuted corncob material with the oil-coated metal, it has been found difficult to completely remove the comminuted corncob material from the metal following mixing. It is an object of the invention to provide an apparatus and method for utilizing comminuted corncob to remove oil from scrap metal and removing substantially all adhering corncob particulate from the scrap metal.
Furthermore, currently the comminuted corncob is mixed with oil-coated parts in a batch-type operation. It is another object of the invention to provide an apparatus and method for continuous processing of oil covered parts.